In drilling operations it is common practice to include one or more valves connected within a pipe string to separate and control the flow of fluid between various sections of the wellbore. These valves are commonly referred to as formation isolation valves (FIV). The formation isolation valve can be constructed in numerous manners including, but not limited to, ball valves, discs, flappers and sleeves. These valves are primarily operated between an open and closed position through physical intervention, i.e. running a tool through the valve to open. To close the valve the tool string and a shifting tool are withdrawn through the formation isolation valve. The shifting tool engages a valve operator that is coupled to the valve moving the valve between the open and closed position.
It is often desired to open the FIV without physical intervention after the valve has been closed by physical intervention, such as by running a shifting tool through the FIV via a wireline, slickline, coil tubing or other tool string. Therefore, it has been shown to provide an interventionless apparatus and method for opening the FIV a single time remotely from the surface. Interventionless is defined to include apparatus and methods of actuating a downhole valve without the running of physical equipment through and/or to the operational valve. Apparatus and methods of interventionlessly operating a downhole valve a single time are described and claimed by the commonly owned United States Patents to Dinesh Patel. These patents include, U.S. Pat. Nos. 6,550,541; 6,516,886; 6,352,119; 6,041,864; 6,085,845, 6,230,807, 5,950,733; and 5,810,087, each of which is incorporated herein by reference.
Some well operations require multiple interventionless openings of the FIV. For example, opening the FIV after setting a packer, pressure testing of the tubing, perforating, flowing of a well for cleaning, and shutting in a well for a period of time.
Heretofore, there has only been the ability to actuate a FIV remotely and interventionlessly once. Therefore, the interventionless actuator can only be utilized after one operation. Further, if the single interventionless actuator fails it is required to go into the wellbore with a physical intervention to open the FIV. This inflexibility to remotely and interventionlessly open the FIV more than once or upon a failure can be catastrophic. In particular in high pressure, high temperature wells, deep water sites, remote sites and rigless completions wherein intervention with a wireline, slickline, or coiled tubing is cost prohibitive.
It is therefore a desire to provide a multiple, interventionless actuated downhole valve. It is a further desire to provide a multiple, interventionless actuated downhole valve wherein each actuating mechanism operates independently from other included interventionless actuating mechanisms.